Thermoform packaging machines may include a forming station that forms one or a plurality of connected packaging troughs in a bottom film by thermoforming. Subsequently, the packaging troughs are filled with products to be packed, e.g. with foodstuffs, and closed (sealed) in a sealing station with a top film. Especially in the field of food packaging, it is common practice to extract (evacuate) the atmospheric air from the filled package and to supply to the packages a suitable (protective) gas prior to sealing the package. When a suitable gas is chosen, then the shelf life of the foodstuffs can be increased.
DE 10 2007 047 058 A1 discloses that an edge area of the bottom film that includes openings through which atmospheric air can be extracted from the spatial areas located between the packaging troughs and the top film prior to sealing in the sealing station. Prior to sealing, the packages have been supplied a suitable gas through additional openings in the bottom film.
DE 1997 665 U discloses a thermoform packaging machine with a forming station, wherein the forming station includes a thermoforming tool comprising a forming tool upper part and a forming tool lower part for forming packaging troughs in a bottom film. The thermoforming tool comprises a blade for cutting slits into the bottom film parallel to the feed direction of the bottom film. Through said slits, the packages can then be evacuated in a downstream sealing station.